Yes people here have talked about this vehicles potential short commings (long reload particularly), but adding it in BR 4 isnt terrible of an idea - yes we already have a KV2 in BR3 which is essentially having the same shortcomings - BUT apparently it can use a HEAT round with insane 250mm of penetration!
90mm of just slightly angled armor is “okay” for a BR4 vehicle,
being a SPG and having a very poor reload speed should justify it having a massively powerful gun,
also it could mount a dshk heavy MG like IS2.
I personally think every nation in every BR should get access to some tank destroyer that has it easier to destroy heavy tanks when getting up tiered.